1. Field of the Invention
The present invention relates to novel polyalkylene guanidine salts or polyalkylene biguanidine salts having a branched silane compound and a method for preparing them. Also, the present invention is concerned with uses of polyalkylene guanidine salts or polyalkylene biguanidine salts having a branched silane compound as antimicrobial agents.
2. Description of the Prior Art
Generally, antimicrobial agents are referred to as functional substances which are able to prevent a human being or other objects from being infected by microorganisms including bacteria, fungi and pathogens. Such function comes from antimicrobial agents which are applied to substances such as fibers, wood, paper, glass, resins and metals and thus protect them against the microorganisms. For example, the antimicrobial agents for fibers include organic compounds such as quaternary ammonium salts (J. Appl. Polym. Sci., Vol. 37, no. 10, 1989, pp 2837-2843), quaternary ammonium silane salts (Japanese Patent Laid-Open Sho 61-15188), various higher organic acids, chitosans (deacylated chitin) (Japan, Dye Industry Vol. 41, no. 4, 1993, pp 9-15), chlorhexidine, polyhexamethylene biguanidine salts (Japanese Patent Laid-Open Hei 7-82663), acrylonitrile copper sulfate complexes and inorganic compounds such as Ag-, Cu- or Zn-impregnated zeolite. These antimicrobial agents for fibers are required to exhibit a safety for the human being, stability and wash fastness for fibers, in addition to being of excellent antimicrobial activity.
Polyhexamethylene guanidine salts or polyalkylene biguanidine salts, well-known antimicrobial agents having a low toxicity, are widely utilized for water treatment such as in swimming pools and spas. The high solubility of said polyhexamethylene guanidine salts or polyhexamethylene biguanidine salts in water makes them elute readily from the materials, leading to the deterioration of the fastness. This is believed to be attributed to the low adhesiveness of the agents to the material, such as fibers, wood, paper, glass, resins and metals.